Well, I would always 'worry' about an almost 400$ earphone, but the CK100 are even more robust than the CK10. The difference of course, is that they cost almost double the price and are slightly bigger. But they use the same cable and have a much better plug. They also have better anchoring to the earphone unit. The CK10 is my favourite overall for sound (probably because it is nigh on neutral), but the CK100 is not far behind. I am not a big vocal and jazz listener, so atmosphere isn't as important to me.
But, among all 300-400$ earphones on the market, the CK100 represents the best value since it sounds good and is built to withstand years of use. Still, I would not go out of the way trying to crack the hard plastic and titanium casing. Nor would I through it around. The CK10 carrying case is much better. Neither of mine came with a wax loop
